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(No Model.)

W. H. SAWYER.

ELECTRIC CABLE.

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UNITED STATES PATENT OFFICE.

IVILLIAM II. SAVYER, OF PROVIDENCE, RHODE ISLAND, ASSIGNOR TO TIIEAMERICAN ELECTRICAL WORKS, OF SAME PLACE.

ELECTRIC CABLE.

SPECIFICATION forming part of Letters Patent No. 473,352, dated April19, 1892. Application tiled October 27, 1891. Serial No. l110.010l (Nomodel.)

To all whom t may concern,.-

Beit known that I, WILLIAM H. SAWYEE, a citizen of the United States,and a resident of Providence, in the county of Providence and State ofRhode Island, have invented new and useful Improvements in ElectricCables; and I do hereby declare the following to be a full, clear, andexact description of said invention, reference being had to theaccompanying Io drawings, and to the letters of reference markedthereon, which form a part of this specification.

My invention relates to certain improvements in electric cables, whichis designed I 5 particularly for telephone and telegraph service, theobject of my invention being the production of a cable of low-inductivecapacity and high insulating properties, combined with cheapness ofconstruction and increased lightness and flexibility.

I attain the above object by means of the construction hereinafterdescribed, and which consists, essentially,in interbraiding or weaving aseries of insulated wires or conductors with a suiiicient quantity ofsuitable iibrous material into a flat continuous strip or ribbon andthen twisting or winding said strip or ribbon into a spirally-tubularform, leaving a central air-space, the interbraiding of said wires orconductors with the fibrous material being such as to provide an openmesh between the wires, the wires in such strip being arrangedequidistant to each other to secure the greatest separation ofconductors in the smallest space, and upon such spiral tube is adaptedto be wound a series of successive strips or ribbons similarlyconstructed, each successive stripy or ribbon being wound in a reversedirection to that of each underlying section, and the cable thusconstructed adapted to be inclosed in a lead sheath or other suitablecovering, all as will hereinafter be more fully described, andspecifically pointed out in the claims.

In the accompanying drawings, Figure l represents a plan view of asection of wires interbraided with iibrous material into ccntinuous flatstrip or ribbon; Fig. 2, a front elevation of a spiral tube formed fromsaid strip or ribbon; Fig. 3, a similar View showing asimilarly-constructed strip superimposed spirally upon the first spiraltube, only in a reverse direction; and Fig. 4;, a transverse sectionalview of the complete cable.

Similar letters of reference indicate like parts in the several iiguresof the drawings.

In the practice of my invention a suitable number of insulated wires orconductors a, preferably four in number, are interbraided or woven atsuitable distances apart with fibrous material into a continuous iiatstrip or ribbon, which is then twisted or wound into a spiral tube A,leaving a central air-space through the same. The insulated wires orconductors are so interbraided or woven with the brous material as toform an openmesh work between the wires, and when the said strip orribbon is twisted into a spiral forni the Wires are all approximatelyequidistant, thereby securing the lowest inductive capacity between thesame. Upon the spiral tube A thus formed is adapted to be Wound astripor ribbon similarly constructed as that of the first section; but thesame is wound on in a reverse direction to that of the first, thussecuring the greatest separation ofconductors within the least possiblespace.

In forming the complete cable a number o sections constructed as abovedescribed are grouped together and inclosed within a lead sheath orother suitable covering, or a series of successive flat strips orribbons carrying the interbraided wires or conductors may be wound uponthe spiral tube A until the cable is built up to the desired diameterand then inclosed within a lead sheath or other suitable covering, eachstrip or ribbon being wound on in a reverse direction to that of eachunderlying section and the spirals or convolutions of the wires orconductors of each successive layer running in reverse directions tothose of the adjacent layer.

Having thus described my invention, what I claim as new and useful is l.An electric cable formed of a number of sect-ions grouped together, eachsection being composed. of a series of insulated wires orconductorsinterbraided with fibrous material into a continuous flat strip orribbon, which is wound or twisted into a spiral tube having a centralair-space, and one or more strips or ribbons similarly constructed beingwound IOO upon said spiral tube in reverse directions tions to eachother to build up the desired and the Whole inclosed within va leadsheath diameter of cable and the whole inclosed or other suitablecovering, substantially as Within a lead sheathor other suitablecoverspecified. Y ing, substantially as specified. I5 5 2. An electriccable formed of a series of In testimony whereof Iaflix my signature ininsulated wires interbraided with fibrous mapresence of two subscribingwitnesses.

terial into a continuous fiat strip or ribbon which is wound or twistedinto a spiral tube WILLIAM H' SAWYER' [L' S'] having a centralair-space, and a series of suc- Witnesses:

1o cessive stri ps or ribbons similarly constructed GILMAN E. J OPP,

wound upon said spiral tube in reverse direc- CHARLES H. WAGENSEIL.

